Diquat
Zachary Water System
Diquat is a herbicide used on potato crops and aquatic weeds.
20
Samples
0
Samples exceeding legal limit (MCL)
0
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | N/A | 0 | 0 | N/A |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | ND | 10 | 0 | ND |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | ND | 2 | 0 | ND |
| 2019 | ND | 8 | 0 | ND |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 6 ppb
The EWG Health Guideline of 6 ppb for diquat was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cataracts.
EPA Maximum Contaminant
Level (MCL) 20 ppb
The legal limit for diquat, established in 1992, was based on a toxicity study in laboratory animals conducted in the 1980s.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2016-01-12 | 35225030003 | ND |
| 2016-01-12 | 35225030003 | ND |
| 2016-07-26 | 35256952004 | ND |
| 2016-07-26 | 35256952003 | ND |
| 2016-07-26 | 35256952001 | ND |
| 2016-07-26 | 35256952002 | ND |
| 2016-07-26 | 35256952003 | ND |
| 2016-07-26 | 35256952004 | ND |
| 2016-07-26 | 35256952002 | ND |
| 2016-07-26 | 35256952001 | ND |
| 2018-11-26 | 35433146001 | ND |
| 2018-11-26 | 35433146001 | ND |
| 2019-06-18 | 35476846001 | ND |
| 2019-06-18 | 35476846004 | ND |
| 2019-06-18 | 35476846003 | ND |
| 2019-06-18 | 35476846002 | ND |
| 2019-06-18 | 35476846001 | ND |
| 2019-06-18 | 35476846004 | ND |
| 2019-06-18 | 35476846003 | ND |
| 2019-06-18 | 35476846002 | ND |